


Heretic Lust

by RebelNoun



Category: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: Cunnilingus, F/M, First Time, Plot What Plot/Porn Without Plot, Vaginal Sex
Language: English
Status: Completed
Published: 2019-09-16
Updated: 2019-09-16
Packaged: 2020-10-20 00:09:07
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,140
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20666078
Author URL: https://archiveofourown.org/users/RebelNoun/pseuds/RebelNoun
Summary: It had only been a few days, but by then everything had spiraled out of their control, and it was time to let carnal feelings take the reigns.Contains spoilers from the Seteth/Flayn A support.





	Heretic Lust

**Author's Note:**

> Let it be known that this pair is the one that got me to break my vow of Never Writing Smut, Never Ever.
> 
> In other words, this is my first smut (and likely only) smut fic so please be gentle ;_;

"Byleth," he murmured, pressing his forehead to hers, "if you don't want this-"

"Believe me, Seteth, I would've said something by now if that were the case," she interjected coyly. "Now shut up and kiss me."

Oh, how things had snowballed over the past few days. And truly, they had, but the speed at which they progressed from confessions to current events was the last thing on their minds.

Seteth forced Byleth back onto the bed with a fierce kiss, pinning her arms by her side. He could feel her struggling to simply touch him, whimpering and squirming at each tender kiss he planted on her neck and breasts.

"Patience," he chided. "You seem to be forgetting how long _I_ have had to wait for this."

To Byleth's frustration, he made good on his promise to take his time. He had littered her entire torso with bite marks and hickeys, and so the light, feathery kisses that he planted on her inner thighs were a pleasant surprise.

She wasn't ready, then, when she felt his teeth graze across her clit, drawing out an involuntary squeal of pleasure.

Seteth's grip on her wrists finally relented as he reached up to toy with her nipples, pinching and twisting as he massaged her breasts in circles. Byleth took the opportunity to grab a fistful of hair, tugging just enough to draw out a moan. The vibration of it alone was nearly enough to send her over the edge. She could feel herself trembling as her breathing became shallow gasps. Seeing his face sandwiched there between her thighs, tongue working tirelessly…

The look he shot her while his face was buried was undeniably sexy, and more than enough to make her lose her grip on reality.

Her orgasm washed over her, warmth emanating from her core. "Seteth," she choked out, hardly able to contain herself. She felt his smile as he looked up at her.

"Yes?" The grin on his face was a playful one, as he brought himself to straddle her hips. There was a question in the air, unasked, but one that Byleth was all too eager to provide an answer to.

"Please," she breathed, propping herself up and draping her arms around his neck. "I want you." She brought him in for a deep kiss, tasting herself on his lips. "Please, take me, Cichol."

Hearing his name, his true name, spoken with such reverence made his cock twitch. The gentle playfulness in his eyes was replaced by a nearly feral hunger and he brought her in for yet another fierce kiss, biting her lip hard enough to draw blood - not that either of them cared. "If you want me to take you," he moaned between kisses, "then I shall happily oblige."

He spun her around with ease, pushing her into the mattress. Leaning to reach her ear, he whispered, "What do you want?"

Byleth couldn't help but let out a muffled whimper into the mattress.

"I'll ask again. What do you want?" he prodded, taking her hair and tugging so that he could see her face. He wanted to hear her beg.

"Please, Seteth-"

"Am I Seteth?" he growled, pushing her even further into the mattress as his free hand landed against her ass. The ensuing frustrating cries were music to his ears.

"Cichol, please, I...I want you to fuck me. Please," she whimpered, trying - and failing - to reach a hand between her legs to play with herself.

She gasped as he entered her - he was far girthier than she had initially thought. Not that it mattered, as everything felt so good and _right_ in that moment. A sharp tug at her scalp brought her rocketing back to reality, and she felt Seteth’s breath on the side of her neck, hot and shallow.

“Be careful what you wish for,” he murmured, before placing his lips to her neck, biting and sucking until a rather sizable hickey formed. With one hand, he held both of her wrists behind her back, and used the other to push her shoulders ever deeper into the mattress.

She had seen him fight, so she knew he was strong, but experiencing it like this was positively electrifying. “Please...I want...I need…” she whimpered, hardly able to form anything resembling a coherent thought. Goddess, he was being such a tease, varying the speed of his thrusts to bring her to her precipice, but never quite to climax.

Without warning, he pulled out and flipped her onto her back, pinning her arms over her head. Seteth allowed himself a moment of reprieve to take in the sight below him as he straddled her. They were both slick with sweat, cheeks flush from Goddess knew what. And that pleading so evident in her eyes…

“Please,” she whined, grinding her hips against his. She was being impatient, but at this point he no longer cared. When he pushed himself in again, bringing their hips flush together, she saw stars.

It didn’t take long after that, moaning into their kisses as they both came together. Seteth rolled himself off of her, taking care to not pin Byleth’s arm in the process. She rolled over herself, nuzzling into his chest.

“Well?” he hummed, lazily stroking her hair. He chuckled to himself as he heard what he thought was snoring emanating from his chest. Placing a soft kiss on her crown, he shuffled quietly off the bed and made his way to the bathroom. _Goddess help me_, he thought, looking at the mess of emerald hair atop his head. A fresh bath for him didn’t take long, and he took the liberty of drawing a second one for whenever Byleth decided to wake up. _She may not truly be one, but she plays the part of a Child of the Goddess incredibly well_, he mused, gazing at a Byleth who was tangled up in his sheets sound asleep.

He decided he’d handle her meetings for the day.

***

After hearing the door latch shut, Byleth buried her head in the pillows, letting out a long, exasperated groan. Though it had been over five years, she could practically hear the scolding she would be getting from Sothis.

_You’re in the middle of a war, and _this_ is what you’re doing? Fraternizing with who might as well be your right hand? Why, if you knew the whole story I’d bet you’d be regretting all of this right now!_

She lazily pushed herself off the bed, heading towards the bathroom, smiling upon the realization that Seteth had already filled the tub for her. Luckily enough, it was still warm, and it smelled of lavender and peppermint. It dawned on her as she sank into the water that she would need a fresh set of clothes.

She didn’t care. After all, that’s what her Saint was for.

**Author's Note:**

> am i a coward now? (not @'in anyone, but you know who you are >:3c)
> 
> For the fluff, go see my WIP Heretic Pride!


End file.
